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Lots of questions remain unanswered. 

 

However lots of information was imparted in a  short amount of time. Hopefully the OP will manage to work their way through it all at some point. 

 

It will certainly be an investment for the future. 

Edited by rusty69
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18 minutes ago, GDaniel said:

Because of work I didn't have time to run the engine. Am I right in assuming that by switching of the the most power draining appliances it gave the batteries time to "recover"?

 

 

There are so many issues it will seem overwhelming to comment on all of them in one single post, so I'll just comment on this bit of your post.

 

1) Batteries do not need "time to recover", they need charging. Note NEED charging. It isn't optional. Well I suppose it is provided you are willing to live with the consequence, which is a steady and possibly quite fast decline in charge capacity of your batteries. This leads to you needing to buy a new set perhaps once a year. The good news is your solar IS charging them, if slowly. Come autumn this will stop when God turns the sun off.

 

2) Needing to go to work and not having time to run the batteries is a trap I too ran into. My batteries would not accept my explanations about how busy I was, and how CRT license terms and social considerations prevented me from charging them sufficiently to preserve them, they just ignored me and degraded anyway. Bustuds.

 

3) Batteries (ordinary one anyway) need charging for hours on end, constantly or at best weekly, to avoid this degradation (called sulphation), and some on here will promote that it is not worth all the effort and one should just buy new batts on a regular basis. Others will give you the impression the sky will fall in if you don't charge them for 25 hours a day. What's right for you will probably be somewhere in between, and it's for you to decide in the light of developing experience where the 'somewhere' lies. 

 

 

 

 

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2 hours ago, MtB said:

 

 

There are so many issues it will seem overwhelming to comment on all of them in one single post, so I'll just comment on this bit of your post.

 

1) Batteries do not need "time to recover", they need charging. Note NEED charging. It isn't optional. Well I suppose it is provided you are willing to live with the consequence, which is a steady and possibly quite fast decline in charge capacity of your batteries. This leads to you needing to buy a new set perhaps once a year. The good news is your solar IS charging them, if slowly. Come autumn this will stop when God turns the sun off.

 

2) Needing to go to work and not having time to run the batteries is a trap I too ran into. My batteries would not accept my explanations about how busy I was, and how CRT license terms and social considerations prevented me from charging them sufficiently to preserve them, they just ignored me and degraded anyway. Bustuds.

 

3) Batteries (ordinary one anyway) need charging for hours on end, constantly or at best weekly, to avoid this degradation (called sulphation), and some on here will promote that it is not worth all the effort and one should just buy new batts on a regular basis. Others will give you the impression the sky will fall in if you don't charge them for 25 hours a day. What's right for you will probably be somewhere in between, and it's for you to decide in the light of developing experience where the 'somewhere' lies. 

 

 

 

 

That really simplifies it for me, so so helpful. I'm getting used to the levels of TLC my beloved boat requires 😅 

3 hours ago, rusty69 said:

That's great.

 

If you still have no loads on, they have a way to go yet before being fully charged, with 12A going in.

 

As the solar season ends, in October ish, you will need to run your engine more to compensate. For how long will depend on how much the batteries are depleted, of course,and the size of your alternator, to a certain extent. 

 

LA batteries take a long time to charge fully, particularly the last bit. Each time you do not do so, you are likely to sulphate the cells, and they will have less and less capacity. 

 

You may get away with a couple of hours a day, but I would give it a much longer run once a week If you can. 

 

I would also try and run it earlier in the day, and let the solar finish them off. Though with dwindling sun, and the heavy loads you appear to have, it may not make much difference. 

 

Make sure you have the engine revs set high enough, as I think Tony mentioned earlier. 

 

To not waste fuel, when they are fully charged, you will need some form of battery monitoring.A simple voltmeter and ammeter will suffice if you monitor tail current.Fancy battery monitor options are also available,but don't rely on the percentage reading at face value unless you understand the parameters it has been set with,and even then take them with a pinch of salt.

 

If you have a smartgauge, make sure it is calibrated before relying on it.

 

Read Tonys battery charging primer.

 

That is all.

 

Communication ends

Really helpful. Thank you. 

No, I'm not in a marina so not hooked up to mains. 

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It’s worth having a handle on the sorts of amp hours you are talking about. ballpark daily 40Ah for a fridge, 50Ah for a freezer, 30Ah for the inverter so 120Ah a day before you start using lights, pumps charging computers and phones, running a router etc.

 

At the 12.3A shown in your latest picture, it will take over 10 hours to replace what you took out just for those 3 items. At the moment, there is about 14 hours between sunrise and sunset, but of course for a good bit of that time there is very little sun. If that 12.3A is taken in full sun near the middle of the day, the average over the whole 14hr day is likely to be half that ie 84Ah, so you are operating at a large deficit which will only get worse as the days shorten.

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14 minutes ago, GDaniel said:

That really simplifies it for me, so so helpful. I'm getting used to the levels of TLC my beloved boat requires 😅 

 

 

You're welcome. Understanding batteries properly is complex and difficult and several posters here who understand them very well, tend not to compromise on the complexity of their technical explanations or make any allowance for any less than perfect understanding in their audience. 

 

One more thing. There is a different type of battery you'll run into pretty quick if you haven't already. Lithium batteries, also know as LiFeP04 batteries. For now, I suggest you skip over/ignore them. Managing lithium batteries requires a level of knowledge one step up from Lead Acid.

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19 minutes ago, nicknorman said:

It’s worth having a handle on the sorts of amp hours you are talking about. ballpark daily 40Ah for a fridge, 50Ah for a freezer, 30Ah for the inverter so 120Ah a day before you start using lights, pumps charging computers and phones, running a router etc.

 

At the 12.3A shown in your latest picture, it will take over 10 hours to replace what you took out just for those 3 items. At the moment, there is about 14 hours between sunrise and sunset, but of course for a good bit of that time there is very little sun. If that 12.3A is taken in full sun near the middle of the day, the average over the whole 14hr day is likely to be half that ie 84Ah, so you are operating at a large deficit which will only get worse as the days shorten.

This ^^^^^^^^

And what Mike has just said.

 

This is why I suggested that you do a power audit, so you can see how much electricity each item uses. I am all but certain that in a few weeks solar will no longer provide for your electrical needs. When that happens, if it has not already, the info in the power audit will help you decide what items you do without. For instance once we get to (say) November you probably won't need a fridge if you get a steel box that you put in the well deck (front deck) to store your perishables in.

 

One thing to keep in mind is that just adding more and more batteries can never solve a lack of charging issue. You have to either alter your charging regime so it provides enough charge or reduce your consumption so such charging as you do have is sufficient.

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1 hour ago, Tony Brooks said:

This ^^^^^^^^

And what Mike has just said.

 

This is why I suggested that you do a power audit, so you can see how much electricity each item uses. I am all but certain that in a few weeks solar will no longer provide for your electrical needs. When that happens, if it has not already, the info in the power audit will help you decide what items you do without. For instance once we get to (say) November you probably won't need a fridge if you get a steel box that you put in the well deck (front deck) to store your perishables in.

 

One thing to keep in mind is that just adding more and more batteries can never solve a lack of charging issue. You have to either alter your charging regime so it provides enough charge or reduce your consumption so such charging as you do have is sufficient.

I have a friend who is an experienced electrician. I'm going to ask him to help me review all the helpful info in your responses (great community) and help me do a power audit. 

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11 minutes ago, GDaniel said:

I have a friend who is an experienced electrician. I'm going to ask him to help me review all the helpful info in your responses (great community) and help me do a power audit. 

I would doubt that an "experienced Electrician" would know much about boats, batteries and marine systems at all. Remember that all the cables on a boat need to be flexibles, preferably tinned copper, not domestic type cable.

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12 minutes ago, GDaniel said:

I have a friend who is an experienced electrician. I'm going to ask him to help me review all the helpful info in your responses (great community) and help me do a power audit. 

 

We always advise being a bit wary of people just referred to as electricians because the standards and regulations for UK boats are very different from those for household or industrial electricians. It is not unknown for installations done on boats by experienced mains type electricians to have to be ripped out and done again. If he is an autoelectrician then he will be more familiar with 12V DC equipment and circuits. This does not mean your friend will not be fine, but he may be well outside his comfort zone. Hopefully he should also be fine in resect of the finding the rating plates on your equipment and the calculations required. However, if you don'tr have the original manuals you may find it difficult to find the Watts or Amps for some of your 12V equipment, if so just tell us what the equipment is, and we can probably give you a fair idea.

 

 

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7 minutes ago, Tracy D'arth said:

I would doubt that an "experienced Electrician" would know much about boats, batteries and marine systems at all. Remember that all the cables on a boat need to be flexibles, preferably tinned copper, not domestic type cable.

 

And the cable sizes required for 12/24V DC systems so excess volt drop is not a problem. Many of the boat cables superficially appear to be far too large for the current they carry, but this is because of the length of cable runs and the volt drop that length causes. Just as an example a cable supplying the domestic water pump sized solely on the basis of current capacity may well cause a domestic water pump to burn out regularly because after the volt drop along the cable the motor can not spin up fast enough to minimize its current draw.

 

Golden Rule - NEVER ever go by a cable's current capacity written on the drum or in a catalogue for any runs over a metre or two, ALWAYS do the volt drop calculation (It is in my course notes).

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22 minutes ago, Tony Brooks said:

 

And the cable sizes required for 12/24V DC systems so excess volt drop is not a problem. Many of the boat cables superficially appear to be far too large for the current they carry, but this is because of the length of cable runs and the volt drop that length causes. Just as an example a cable supplying the domestic water pump sized solely on the basis of current capacity may well cause a domestic water pump to burn out regularly because after the volt drop along the cable the motor can not spin up fast enough to minimize its current draw.

 

Golden Rule - NEVER ever go by a cable's current capacity written on the drum or in a catalogue for any runs over a metre or two, ALWAYS do the volt drop calculation (It is in my course notes).

I'm sure you're right but he manages complex projects so he will be able to help me make sense of some the more technical feedback I've received. Every little helps. 

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1 hour ago, GDaniel said:

I'm sure you're right but he manages complex projects so he will be able to help me make sense of some the more technical feedback I've received. Every little helps. 


Which is fine. I managed a complex EDI messaging system for best part of 10 years - I can’t write code, I don’t understand data networking. Project management is an entirely different skill.

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18 minutes ago, Col_T said:


Which is fine. I managed a complex EDI messaging system for best part of 10 years - I can’t write code, I don’t understand data networking. Project management is an entirely different skill.

Lol. I get it. But he really is a very skilled electrician so I can't see there being any harm in him helping me read some of these very technical posts. Appreciate the candour as always 😆

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3 hours ago, GDaniel said:

I have a friend who is an experienced electrician. I'm going to ask him to help me review all the helpful info in your responses (great community) and help me do a power audit. 

I was an electrician. and I can assure you that 99% of electricians wont have a clue what you are on about unless they are use to battery systems, which are few and far between.

Edit to add. When I say was I retired completely over 20 years ago from working for a living and now boating so much I am still learning.

Edited by ditchcrawler
I did it again
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3 hours ago, GDaniel said:

Lol. I get it. But he really is a very skilled electrician so I can't see there being any harm in him helping me read some of these very technical posts. Appreciate the candour as always 😆

 

 

The thing is, your problems (every newbie's electrical problems) are nothing to do with the electrical installation and everything to do with the user's charging regime.

 

There are very few fields in electrical work where understanding in detail how lead acid batteries behave when pushed to the limits of their performance envelope, hence the scepticism about the probability of him having much more than a sketchy understanding of the issues involved. HST he will prolly understand the points made in this thread so far more easily than you and explain them in more detail to you. Hopefully! 

 

Encourage him to register here and post some probing questions....

 

 

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4 hours ago, ditchcrawler said:

I was an electrician. and I can assure you that 99% of electricians wont have a clue what you are on about unless they are use to battery systems, which are few and far between.

Edit to add. When I say was I retired completely over 20 years ago from working for a living and now boating so much I am still learning.

 

Completely agree with this.

 

I studied electrical engineering to HNC level before starting work for what became BT. I was sent to work on the DC power group. It was totally alien to me, as it was simply not covered in much detail.

 

I quickly learnt what mattered with DC, (selecting cables and bus bars for volt drop rather than current carrying capacity) but it took years to learn the finer points of of lead acid batteries. It is really is no as lost my a black art.

 

Later when BT made me people "multi-skill", the electrician's quickly learnt the basics of high voltage and mechanical engineering, but very few really got to.grips with DC.

 

Even though I spent a career working with batteries, I am still learning of the nuances of using them in boats, where the charge/discharge routine is much more frequent than in most other applications.

Edited by cuthound
To unmangle the effects of autocorrect.
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